Guided Self-Service - Transaction Configuration with Action of 'POS' - Position Change

When a Guided Self-Service Transaction is configured with the Action of 'POS' - Position Change, The Action Reasons are NOT presented to the Manager / User. There appears to be some hard coding to Hide the Action Reasons if the Action is 'POS'. I don't see reference to this in the documentation and NOT understanding why the Action Reasons for 'POS' is being suppressed???